Geological investigations of a part of the crystalline basement in the Baltic Sea have been performed on a drill core collected from the depth of 1092–1093 m beneath the Phanerozoic sedimentary cover offshore the Latvian/Lithuanian border. The sample was analyzed for geochemistry and dated with the SIMS U–Pb zircon method. Inherited zircon cores from this migmatized granodioritic orthogneiss have an age of 1854 ± 15 Ma. Its chemical composition and age are correlated with the oldest generation of granitoids of the Transscandinavian Igneous Belt (TIB), which occur along the southwestern margin of the Svecofennian Domain in the Fennoscandian Shield and beneath the Phanerozoic sedimentary cover on southern Gotland and in northwestern Lithuania. It is suggested that the southwestern border of the Svecofennian Domain is located at a short distance to the SW of the investigated drill site. The majority of the zircon population shows that migmatization occurred at 1812 ± 5 Ma, with possible evidence of disturbance during the Sveconorwegian orogeny.

对波罗的海部分结晶基底的地质调查是在拉脱维亚/立陶宛边界海上生代沉积覆盖层下方1092–1093 m的深度采集的钻芯上进行的。对样品进行了地球化学分析，并用SIMS U–Pb锆石法标明了日期。从这种迁移的粒二长生正片麻岩中继承的锆石核的年龄为1854±15 Ma。它的化学成分和年龄与最古老的跨斯堪的纳维亚火成岩带（TIB）相关，它们沿芬科斯堪迪亚盾构Svecofennian地带的西南边缘以及哥得兰岛南部和立陶宛西北部的生代沉积层之下。建议Svecofennian域的西南边界距离被调查的钻探点西南部不远。多数锆石种群显示，迁移发生在1812±5 Ma，可能有证据表明在Sveconorwegian造山运动中发生了扰动。